About the random reactor generator

Our random reactor generator gives you a random reactor idea. It uses a few acronyms. This page explains them.


Most coolants are self-explanatory but there are a few things worth mentioning:

  • CO2 is carbon dioxide
  • H2O is water or steam or ice or plasma-water
  • D2O is deuterium-dioxide, aka heavy water. It uses hydrogen isotopes that have one extra neutron.
  • exotic covers all gasses not listed just to be exhaustive

Coolants can additionally in any phase depending on their temperature and pressure. So we include solid, liquid, gas, and plasma forms of all coolants. Technically we could do this to moderators and fuel as well but we chose not to.


The fuel forms are fairly well-known, but we used some acronyms in the type of fuel:

  • HEU – High-enriched uranium (anything enriched >20%)
  • WGPu – Weapons-grade plutonium, often leftover from weapons programs
  • RGPu – Reactor-grade plutonium, often from reprocessed nuclear waste
  • HALEU – High-assay low-enriched uranium; a easy word to say any uranium enriched between 5 and 20%.
  • LEU – low-enriched uranium; enriched but not over 5%
  • DU – depleted uranium; mostly U-238, often tails of an enrichment plant
  • NU – natural uranium; right out of the dirt
  • UNF – Used nuclear fuel; just another blanket term for spent nuclear fuel/nuclear waste

All combinations

There are currently 3,855,600 different reactor concepts in the database. If you want to see them all printed out, download this giant zip file.

But why?

This is kind of a tongue-in-cheek hat-tip to a common misconception of nuclear amateurs who think that a reactor idea alone is a big part of improving nuclear energy’s service to humanity. In reality, reactor concept ideas are a dime a dozen, while developing and deploying reactors is the challenging part. Innovations and advances in reactor design process, reactor construction, and reactor operation are needed vastly more than new reactor concepts. We hope people will focus most efforts there rather than on patenting replicas or minor twists to old concepts.

See Also